Plastic is a nice example of a material with two different BSDFs mixed together.
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Avoid having more than one layer set to a weight of 100 in Additive mode. A material with three layers, two of which are set to Additive and have a weight of 100, will look unrealistically reflective. And it will also add to the render time. This does not apply to layers in Normal mode.
fiberglass by rivoli | pool tiles by brunno_sdi |
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